Centering means for drilling machine spindles



June 18, 1940. I G. MOLLER 2,204,811

CENTERING MEANS FOR DRILLING MACHINE SPINDLES Original Filed Jan. 4, 1957 2 Sheets-Sheet 2 Patented June 18, 1340 UNITED STATES PATENT OFFICE CENTERING MEANS ron DRILLING MACHINE SPINDLES Georg Miiller,

signor to Herbert Lindner,

Germany Berlin-Neukoelln, Germany, as-

Berlimwittenau,

Original application January 4, 1937, Serial No. 119,042. Divided and this application June, 8,

1939, Serial No. 278,133.

In Germany August 4 Claims. (Cl. 17-5) This invention relates to centering means atthis character especially adapted for use in co-' ordinate drilling machines and wherein optical means are employed for sighting a point exactly in alinement with the axis of the drill spindle.

Heretofore attempts have been made to provide optical means for this purpose and in certain of the proposed devices an angled microscope was fitted to the lower end of the drill spindle, either by providing the microscopic instrument with a tapered attaching member or by providing some other means for securing the instrument to the lower end of the spindle. This was found objectionable because it necessitated application and removal of the microscope-each time the drill was" set and there was thus not only much delay entailed, but there was great danger of injury to the microscope, due to its being constantly handled.

Attempts were made to overcome this difliculty by mounting the microscope in the hollow spindle with the eye-piece at the top of the spindle. While this allowed the microscope to be made a fixed part of the drill, it introduced other difli culties because thetop of the drill spindle in most coordinate drilling machines is much higher. than the eye of a' machinist standing at the drill and the microscope could only be used by climbing on the drill or one ladder or box. Therefore, in such cases, it would be impossible for the machinist, to look in the eye-piece of the microscope and to manipulate simultaneously the means for eiiecting the adjustment of the work table and the drilling head. Furthermore, it was found advisable, in many machines, to remove the eye-piece'during the drilling operation, due.

to the structure and operation of the drive for the machine. In such cases, there still existed the danger of injury to the instrument.

One importantobject of the present invention is to provide a novel arrangement of microscope and drill spindle wherein the microscope is carried by the machine in permanent operative relation thereto.

A second important object of the invention is to provide a novel arrangement of microscope and drill spindle wherein the object glass is within the hollow drill spindle and the eye-piece extends laterally of the spindle, a sight opening being provided in the wall of the spindle and a reflector allned therewith.

A third important object of the invention is to provide a novel arrangement of this kind wherein the line of collimation of the microscope will coincide exactly with the axis of the spindle and wherein the adjustment of the object glass to and from the work will be effected by the usual operations of lowering and raising the spindie.

A fourth important object of the invention is to provide means whereby the sight opening in the spindle wall may be alined with the eyepiece end of the microscope. its movement to such position being indicated by suitable index means With the foregoing and other objects in view,

. theinvention consists in the details of construction, andin the arrangement and combination of parts to be hereinafter more fully set forth and claimed. In describing the invention in detail, reference will be had to the accompanying drawings forming part of this application, wherein like characters denote corresponding parts in the several views. and which-'- Figure 1 illustrates a front elevation of a portion of a drilling machine head embodying the invention; i I

Figure 2 illustrates a section of the line (1-2) of Fig. 1;

Figure 3 illustrates a fragmentary section of the line e-d of Fig. 2;

Figure 4 illustrates a fragmentary section on a plane corresponding substantially to that identified by the line 13-11 of Fig. 2;

Figure 5 illustrates an enlarged fragmentary detail of the manner of adjusting the line of collimation of the microscope with respect to the axis of the drill spindle and its sleeve.

In the embodiment of the invention here disclosed, there is provided a tubular or hollow drill spindle I having the usual tapered socket lb at its lower end, this socket being of standard taper to receive the correspondingly standardized taper tang ,of a drill. A portion of the drilling machine head is indicated at B and in-this head is an accurate vertical bore 8a wherein is fitted a vertically slidable spindle sleeve 2 provided with a tapered lower bearing 3 and a cylindrical upper bearing 4. In these bearings fit corresponding journal portions 3a and 8a formed on the spindle l. A socket 2a. is formed at the upper end of the sleeve 2 and seated in this socket is a nut 2b which is screwed on the upper end of the spindle and serves to hold it in position for a close running fit of its journals in the bearings 55 and 4. These parts are carefully fitted to prevent any eccentricity of movement of the drill spindle, that is, to insure that the axis of the drill, when held in the socket lb, will coincide with the axis of rotation of the spindle. On the upper end of the spindle is fitted a drive pulley '5 driven by suitable means (not shown) the spindle being held to slide vertically through the pulley, while revoluble therewith, by spline means In. The sleeve 2 is provided with a longitudinally extending rack l wherewith meshes a pinion 6 carried on a shaft 6a rotated by means present ly described. By means of this rack and pinion the sleeve 2 is raised and lowered.

There is fixed on the shaft 6a a worm wheel ll wherewith meshes a worm I ll rotated by an adjusting handle 9 mounted on the head 8. Mounted in the spindle I is an object glass tube I2 which carries at its.l0wer end an object glass l3 while a reflecting device M, such as a mirror or prism, is located at the upper end of the tube l2. This tube is held in proper position by suit-' able means such as the pins l5 and secured against rotation by a set-screw l6 screwed through the wall of the spindle I and engaging the side of the tube l2. In the spindle. l is provided a sight opening l9 which is positioned so that light entering the tube l2 through the glass I3 will be reflected through the sight opening I 9. In the sleeve 2 is also formed a sight opening 20 which is on a vertical level with the sight opening l9. In order to determine when the sight opening I9 is rotatably in registry with the sight opening 20, there is provided on the lower end of the spindle l a collar if which is provided with an index mark 26 which, when brought into registry with an index 21, indicates that the two sight openings are alined.

Packing rings 2| and 22 are arranged between the spindle and sleeve above and below the sight opening IS in order to prevent lubricant used between the spindle and sleeve from finding its way into the microscope.

The machine head 8 is provided with a vertical rib 32 having opposed guide slots or grooves 32a in its side faces. Mounted on this rib is a saddle 3| carrying guide ribs 3Ia engaging slidably in the slots or grooves 32a. Thus, the saddle may slide vertically on the rib 32. A microscope tube lle, of the known construction as before, passes through this saddle so that its inner end enters a vertical slot 300, formed in the saddle. A pin 33 has a reduced end 33a fixed in the sleeve 2 above the opening 20 and the saddle is provided with an opening 330 wherein removably fits the head of a screw 33b screwed into the end of the pin 33, the screw 33b having a reduced end 33d fitting into the pin 33, thus connecting the saddle and sleeve 2. Thus, the sleeve and saddle are connected together and move in unison through a vertical plane. At the same time, by

removing the screw 33?) they may be moved independently.

In order to move the saddle and sleeve vertically without relying entirely on the screw 33b, the modified arrangement of Fig. 5 is provided. On the shaft 6a is fixed a bevel gear 35 which meshes with a bevel gear 34 mounted on a shaft 34a carrying an operating handle 9a. On the shaft 34a is also fixed a gear 38 which meshes with an idler gear 39, which meshes in turn with a gear 40 mounted on a shaft 40a and adapted to be engaged with and disengaged from the shaft 20a by manipulation of the pull-pin 3, the construction being well known and not deemed necessary to be described in detail. On the shaft 50a is also fixed a gear M which meshes with a rack 42 secured to the side of the saddle 3i. there is mounted on the shaft 34a a worm wheel 3? provided with suitable means (not shown), for engagement with and disengagement from the shaft. This gear 31 is engaged by a worm 36 which is driven in the usual manner from the power feed of the machine. It will be noted that the saddle may move independently of the sleeve 2 by disengagement of the gear 40 from the shaft 40a, but may be caused by the gear arrangement to move in unison with the sleeve.

With either of the arrangements, it willbe seen that the light rays R pass through the microscope from the center point C and by proper adjustment of the sleeve 2 and eyepiece llb the center point C may be brought sharply into focus in the field of vision of the microscope. Then by manipulating the table feeds of the machine, this point C may be brought into registry with the intersection of the line Mia and thus to liein the line of collimation of the microscope and axis of rotation of the spindle and drill tool.

There have thus been provided simple and efficient means of the kind described and for the purposes specified.

It is obvious that changes may be made in the form and construction of the invention without departing from the principles involved. It is not therefore desired to confine the invention to the exact forms shown and described, but it is desired to include all forms which come within the scope of the appended claims.

The details of the hair ring iii are illustrated in Fig. 5 and the ring ll] carries a transparent plate liib having a pair of hair-lines IBa inserted thereon. This ring may be adjusted to bring the intersection of the lines lBa into the'line of collimation of the microscope by means of three set-screws 28 passing through the tube lid and engaging the ring at 120 intervals.

1 claim:

1. In combination with a drilling machine having a head carrying a vertically movable spindle sleeve and having a drill spindle rotatably mounted in said sleeve, said sleeve and drill spindle having alinable sight openings and cooperating means being provided on the head and spindle for indicating alinement of said openings, a tube fixed in the hollow spindle and having an opening registering with the sight open- Also 7 ing in the spindle, an object glass at the lower ably mounted in said sleeve, said sleeve and drill spindle having alinable sight openings and cooperating means being provided on the head and spindle for indicating alinement of .said

openings, a tube fixed in the hollow spindle and having an opening, registering with the sight opening in the spindle, an object glass at the lower end of said tube, a reflector above said glass and opposite the tube opening, a vertically slotted guide rib on said'head, a saddle slidably mounted on said rib, an eye-piece carried by said saddle and movable with the saddle, said eye-piece being normally alined with the sight opening in the sleeve, and meansto raise and lower the saddle and sleeve simultaneously, said means including a releasable element whereby the saddle and eye-piece may be moved independently of the sleeve.

3. In combination with a drilling machine having a head carrying a vertically movable spindle sleeve and having a drill spindle rotatably mounted in said sleeve, said sleeve and drill spindle having alinable sight openings and cooperating means being provided on the head and spindle for indicating alinement of said openings, 9. tube fixed in the hollow spindle and having an opening registering with the sight opening in the spindle, an object glass at thelower end of said tube; a reflector above said glass and opposite the tube opening, a vertically slotted guide rib on said head, a saddle slidably mounted on said rib, an eye-piece carried by said saddle and movable with the saddle, said eyepiece being normally alined with the sight opening in the sleeve, means to raise and lower the saddle and sleeve simultaneously, and packing means above and below the sight opening between the drill spindle andv sleeve.

4. Incombination with a drilling machine having a head carrying a vertically movable spindle sleeve and having a drill spindle rotatably mounted in said sleeve, said sleeve and drill spindle having alinable sight openings and cooperating means being provided on the head and spindle for indicating alinement of said openings, a tube fixed in the hollow spindle and having an opening registering with the sight opening in the, spindle, an object glass at the lower end of said tube, a reflector above said glass and opposite the tube opening, a vertically slotted guide rib on said head, a saddle slidably mounted on said rib, an eye-piece carried by said saddle and movable with the saddle, said eye-piece being normally alined with the sight opening in the sleeve, means to raise and lower the saddle and sleeve simultaneously, said 

